flag is available since Ruby 2.3

korny · korny · commit 860c2e132d2e · 2017-09-03T10:34:33.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -16,7 +16,7 @@ branches:
   only:
     - master
 before_script:
-- if (ruby -e "exit RUBY_VERSION.to_f >= 2.4"); then export RUBYOPT="--enable-frozen-string-literal"; fi; echo $RUBYOPT
+- if (ruby -e "exit RUBY_VERSION.to_f >= 2.3"); then export RUBYOPT="--enable-frozen-string-literal"; fi; echo $RUBYOPT
 matrix:
   allow_failures:
     - rvm: ruby-head
